Cotter key



Feb. 79 1951 J. A. MaGLEAN, JR., ETAL 2,543,414

CUTTER KEY Filed Jan. 24,'1945 Patented Feb,I 27, 1951 UNIT STATES PATENT otros COTTER KEY Application .iannary 24, 1945, Serial No. 574,338

1 Claim.

Our invention relates to Cotter keys and has for its object the provision of a cotter key that is of simple sturdy construction and economical to manufacture and easy to install, which, after being properly placed in an appropriate Cotterreceiving hole of a bolt or pin or other part with which it cooperates, will have a multiplicity of surfaces of substantial area forcibly engaging and held against the wall of the hole, to the end that rattling of the Cotter key in the hole, and consequent Wearing of the Cotter key and the wall of the hole, will be eliminated.

A salient feature of the present invention is the manner in which the legs of the cotter key move as levers, on fulcra located intermediate the ends of the legs and afforded by opposed contacting portions of the legs, when the cotter key is properly placed in the Cotter-receiving hole of the bolt or pin or other part with which it is to cooperate.

Other features, objects and advantages of our present invention will appear from the following detailed description wherein reference is made to the accompanying drawings.

In the accompanying sheet of drawings:

Fig. 1 is an edge View, Fig. 2 is a side View, and Fig. 3 is an end view of the Cotter key as it appears before being placed in the Cotter-receiving hole of a bolt, pin or other part with which it is to Cooperate;

Fig. 4 is a sectional view illustrating the Cotter key as it appears after being driven home into the Cotter-receiving hole of a bolt, pin or other part with which it cooperates; and

Fig. 5 is a View, similar to Fig. 4, depicting the installed Cotter key as it appears after the free ends of its legs have been widely spread apart.

Similar Characters of reference refer to similar parts throughout the several views.

Referring first to Figs, 1, 2 and 3, it will be observed that our improved cotter key Consists of a piece of half-round metal wire that has been return bent to denne the head-loop l and provide the legs 2 and 3. The flat faces of the legs are presented to each other and leg 2 preferably is somewhat longer than leg 3. The half-round f wire usually will be of one of the steels heretofore found suitable for Cotter key service.

In the formation of the Cotter key, the semicylindrical faces of its legs are indented. as in-A dicated at 4 4, to form on the iiat faces of the legs transversely extending beads or pretuberances 5 5. 4These beads or protuberances 5 5 are intended initially to have line Contact 2 with each other, as illustrated, and preferably Curve away from their line of contacts toward the ends of the legs.

Except for the indentations E fi and beads or protuberances 5 5, the legs are substantially straight, with their portions 2a and 3a converging away from beads or protuberances 5 5, and with their portions 2b and 3b diverging away from such beads or protuberances 5 5. The free end of leg 3 preferably lies immediately adjacent to the at face of leg 2.

In Figs. 4 and 5, We have depicted at t a bolt, pin or other part provided With a hole in the nature of a bore 'l for reception of the ootter key. The distance between the points A and B, on the portions 2a and 3a of the legs, is preferably substantially equal to or slightly less than the diameter of the bore l; whereas the distance between the points C and D, on the portions 2b and 3b of the legs, is preferably definitely greater than the diameter of the bore l.

After the free ends of the legs 2 and 3 have been inserted in bore l, the cotter key freely may be moved into such bore until the portions 2b and 3b of the legs have started to enter the same. Driving the Cotter key further into bore l causes movement ofthe legs 2 and 3 as levers on fulcra constituted by the contacting beads or protuberances 5 5, the portions 2b and 3b of the legs being squeezed together, with some consequent constriction of head-loop i, to .locate their semi-cylindrical faces in snug forcible Contact with the wall of bore l', and the portions 2a and 3a of the legs separating to place their semi-cylindrical faces also in snug forcible con. tact with the wall of bore "l, See 4. When the Cotter key is formed of relatively soft metal stock, as usually will he the case, the driving home of the Cotter key will cause the opposed surfaces of the beads or protuberances 5 5 to flatten somewhat, thus transforming their original line Contact to a forcible snug face-toface contact between surfaces of substantie.1I area. The free ends of the Cotter key legs Conventionally may be spread apart, as depicted in Fig. 5.

The snug forcible contacts between the wall. of bore 7 and the semi-cylindrical faces of the leg portions 2a, 3a, 2b and will be maintained indeiinitely despite that the bolt, pin or other part 5 be snhiected to excessive and/or con tinuous vibration.

In manufacturing the Cotter key.` the beads or protuberanr-es 5 5 preferably are first nroduced on a suitable length of wire which then is returned bent and otherwise conformed to 3 provide the head-loop l, and to place the beads or protuberances 5 5 in opposed immediate juxtaposition.

Having thus illustrated and described our invention, what we claim as new and desire to secure by Letters Patent of the United States is:

A Cotter key adapted to fit snugly in holes ranging in size between predetermined maximum and minimum limits and having a pair of legs that are connected at corresponding ends and not connected at their other ends, the connected ends of the legs being spaced apart so that the maximum span of the opposed outer surfaces thereof exceeds the maximum limit of the hole size and the other ends of the legs being substantially straight, in practical alignment with the connected ends and lying comparatively close together so that the maximum span o opposed. outer surfaces thereof is less than the minimum limit of hole size, opposed protuberances on 'the legs located nearer said connected ends 'than said unconnected ends so as to be positioned midway in the length of the hole, said protubei'- ances having opposed surfaces curved longitudinally of the legs, substantially flat laterally of the legs and aligned forcibly to press against each other and serve as fulcra on which the legs rock relative to one another as levers when the cotter key is forced into a Cotter-receiving hole of a size between said maximum and minimum limits.

JOHN A. MACLEAN, JR.

BENJAMIN FRANKLXN MONEY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 795,242 Weiss July 18, 1905 996,756 Germonprez July 4, 1911 1,233,195 Creech July 10, 1917 1,244,076 Pfister Oct. 23, 1917 1,336,498 Aylor et al Apr. 13, 1920 1,425,367 Chase Aug. 8, 1922 1,695,433 Gibson Nov. 2, 1926 2,172,852 Reynolds Sept. 12, 1939 2,266,689 Lemison Dec. 16, 1941 

